Predictive visualization of medical imaging scanner component movement

ABSTRACT

An augmented reality system is provided for use with a medical imaging scanner. The AR system obtains a digital image from a camera, and identifies a pose of a gantry of the medical imaging scanner based on content of the digital image. The gantry includes a movable C-arm supporting an imaging signal transmitter and a detector panel that are movable along an arc relative to a station. A range of motion of the movable C-arm along the arc is determined based on the pose. A graphical object is generated based on the range of motion and the pose, and is provided to a display device for display as an overlay relative to the medical imaging scanner.

TECHNICAL FIELD

The present disclosure relates to medical imaging scanner systems, andmore particularly, controlled placement and movement of components ofmedical imaging scanner systems.

BACKGROUND OF THE DISCLOSURE

Healthcare practices have shown the tremendous value ofthree-dimensional (3-D) medical imaging scanner systems such as computedtomography (CT) imaging, as a diagnostic tool in the RadiologyDepartment. These systems generally contain a fixed bore into which thepatient enters from the head or foot. Other areas of care, including theoperating room, intensive care departments and emergency departments,rely on two-dimensional imaging (fluoroscopy, ultrasound, 2-D mobileX-ray) as the primary means of diagnosis and therapeutic guidance.

Mobile medical imaging scanner systems have evolved for non-radiologydepartment use and provide patient-centric 3-D imaging. Small scalemobile systems have evolved for use in the operating room, procedurerooms, intensive care units, emergency departments and other parts ofthe hospital, in ambulatory surgery centers, physician offices, and themilitary battlefield, and which can image patients in any direction orheight and produce high-quality 3-D images. These systems includeintra-operative CT and magnetic resonance imaging (MRI) scanners, andrelated robotic systems that aid in their use or movement. The systemscan include 180-degree movement capability (via movable “C-arms” forimaging). The systems may be particularly useful during surgery or othermedical procedures when a real-time image is desired to guide personnelthrough a medical procedure.

Medical imaging scanner systems require a high level of operator skilland can require calibration operations to properly position the movableimaging components for a patient scan, and which can be complicated whena patient is immobilized on a bed. In an operating room or operatingtheatre, the size and weight of the system and the presence of numerousrequired personnel and other medical equipment can make it difficult toprecisely position the movable imaging components for a scan of apatient without leading to collision of the movable imaging componentswith the patient, personnel, and/or other medical equipment.

SUMMARY OF THE DISCLOSURE

Various embodiments of the present disclosure provide an improved userinterface for operating a medical imaging scanner system.

Some embodiments of the present disclosure are directed to an augmentedreality (AR) system for use with a medical imaging scanner. The systemincludes a processor and a memory which stores program code that isexecutable by the processor to perform operations. The operationsinclude obtaining a digital image from a camera, and identifying a poseof a gantry of the medical imaging scanner based on content of thedigital image. The gantry includes a movable C-arm supporting an imagingsignal transmitter and a detector panel that are movable along an arcrelative to a station. The operations determine a range of motion of themovable C-arm along the arc based on the pose. The operations furthergenerate a graphical object based on the range of motion and the pose,and provide the graphical object to a display device for display as anoverlay relative to the medical imaging scanner.

Various further embodiments are directed to displaying an arcuate objectas an overlay relative to the gantry and with a pose that indicates arange of motion of at least one of the imaging signal transmitter andthe detector panel. A circular object may be displayed with a pose thatindicates an interior region of the movable C-arm that will not becontacted by the at least one of the imaging signal transmitter and thedetector panel when moved along the arc through the range of motion. Thesystem may perform a collision alert action responsive to determiningthat a physical object which is separate from the gantry has a surfacethat extends from a location within the circular object displayed on thedisplay device to another location that is outside the circular object.The collision alert action may include providing another graphicalobject for display as an overlay relative to the physical object andthat identifies the physical object as being a collision risk, and/ormay include communicating a command to the medical imaging scanner thatdisables electronic movement of the movable C-arm at least in adirection that may collide with the physical object. The system maygenerate an animation of the motion of the gantry through its range ofmotion. The system may display virtual imaging signal beams that extendbetween the present locations of the X-ray beam and the detector paneland/or that extend between earlier defined locations of the X-ray beamand the detector panel. These and additional embodiments are describedin further detail below.

Still other related embodiments are directed to another AR system foruse with a medical imaging scanner. The AR system may include astand-alone headset or a headset that is communicatively connected to anAR predictive visualization computer. The AR system includes a camera, adisplay device with a see-through display screen that displays graphicalimages while allowing transmission of incident ambient lighttherethrough, and at least one processor that performs operations. Theoperations include obtaining a digital image from the camera, andidentifying a pose of a gantry of the medical imaging scanner based oncontent of the digital image. The gantry includes a movable C-armsupporting an imaging signal transmitter and a detector panel that aremovable along an arc relative to a station. The operations furtherinclude determining a range of motion of the movable C-arm along the arcbased on the pose. The operations generate a graphical object based onthe range of motion and the pose, and providing the graphical object tothe display screen for display as an overlay relative to the medicalimaging scanner.

When the AR system is a stand-alone headset, the camera, the displaydevice, and the at least one processor are each supported by a headsetframe.

When the AR system uses an AR headset that is communicatively connectedto an AR predictive visualization computer, the AR headset includes anetwork interface, the camera, the display device, and a first processorwhich is configured to perform the operation of obtaining the digitalimage from the camera and an operation of communicating the digitalimage through the network interface toward the AR predictivevisualization computer. The AR predictive visualization computerincludes a network interface configured to communicate with the networkinterface of the AR headset, a second processor which is configured toperform the operations of identifying the pose of the gantry,determining the range of motion of the movable C-arm, generating thegraphical object, and providing the graphical object through the networkinterface toward the AR headset for display on the display screen.

It is noted that aspects described with respect to one embodimentdisclosed herein may be incorporated in different embodiments althoughnot specifically described relative thereto. That is, all embodimentsand/or features of any embodiments can be combined in any way and/orcombination. Moreover, apparatus, systems, methods, and/or computerprogram products according to embodiments will be or become apparent toone with skill in the art upon review of the following drawings anddetailed description. It is intended that all such additional apparatus,systems, methods, and/or computer program products be included withinthis description and protected by the accompanying claims.

BRIEF DESCRIPTION OF DRAWINGS

Other features of embodiments will be more readily understood from thefollowing detailed description of specific embodiments thereof when readin conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective rear view of an imaging system according to someembodiments of the present disclosure.

FIG. 2 is a schematic diagram of an imaging controller system 40according to some embodiments of the present disclosure.

FIG. 3 is a perspective front view of the imaging system of FIG. 1.

FIG. 4 is a perspective view of the imaging system of FIG. 1 in whichthe gantry has been rotated about the X-axis by 90 degrees.

FIG. 5 is a perspective view of the gantry partially showing a cablingarrangement.

FIG. 6 is a perspective view of the gantry showing the cablingarrangement.

FIG. 7 is a side view of the gantry showing the cabling arrangement.

FIG. 8 illustrates a motor assembly for telescopically controlling theC-arms of the gantry.

FIGS. 9A-9G illustrate the 360 degree rotation of the gantry in 60degree increments.

FIG. 10 is a perspective rear view of an AR system with an AR headsetthat displays graphical objects as overlays on a medical imaging scanneraccording to some embodiments of the present disclosure.

FIG. 11 is a side view of the gantry of the medical imaging scanner asviewed through a display screen of an AR headset that displays agraphical object illustrating an interior region of the movable C-armthat will not be contacted by the C-arm when moved through its range ofmotion, in accordance with some embodiments.

FIG. 12 is a side view of the gantry as viewed through a display screenof an AR headset that displays graphical objects illustrating thecollision free interior region of the movable C-arm and indicating thata surgical table has a risk of collision with the C-arm when movedthrough its range of motion, in accordance with some embodiments.

FIG. 13 is a side view of the gantry as viewed through a display screenof an AR headset that displays graphical objects illustrating earlierdefined locations and/or future defined locations of an imaging signaltransmitter and a detector panel, in accordance with some embodiments.

FIG. 14 is a side view of the gantry as viewed through a display screenof an AR headset that displays a virtual imaging signal beam extendingbetween the present locations of the imaging signal transmitter and thedetector panel, and displays another virtual imaging signal beam thatextends between earlier defined locations of the imaging signaltransmitter and the detector panel, in accordance with some embodiments.

FIG. 15 is a block diagram that illustrates components of an AR headsetconfigured in accordance with some embodiments.

FIG. 16 is a block diagram that illustrates components of an ARpredictive visualization computer configured in accordance with someembodiments.

FIG. 17 is a flowchart of operations performed by an AR system inaccordance with some embodiments.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are setforth in order to provide a thorough understanding of embodiments of thepresent disclosure. However, it will be understood by those skilled inthe art that the present invention may be practiced without thesespecific details. In other instances, well-known methods, procedures,components and circuits have not been described in detail so as not toobscure the present invention. It is intended that all embodimentsdisclosed herein can be implemented separately or combined in any wayand/or combination.

When working with medical imaging scanner systems, it may not be safefor users to assume that the pathway of components that move duringmedical imaging is clear, since they may collide with a patient or otherequipment. One approach for avoiding such collisions, is to visuallyestimate whether components of the scanner system will be clear ofcollisions along their range of motion and, if not, to then stop a scan,adjust positioning of the scanner system and/or object in the pathway,and re-start imaging. Another approach is to perform a dry run in whichthe scanner system moves through its entire pathway while observing forpossible collisions, and while the imaging signal transmitter isunpowered. These approaches undesirably consume time, personnelresources, and electrical power, and may lead to unnecessary exposure toimaging signals, such as x-rays, for personnel and patients.

Various embodiments of the present disclosure are directed to animproved user interface for operating a medical imaging system havingmovable scanner components. An augmented reality (AR) system enables auser who is wearing an AR headset or looking at a video monitor of theoperating room scene to visually observe graphical objects that aredisplayed as an overlay on the imaging system to illustrate the range ofmotion of the movable scanner components. The graphical objects mayprovide predictive visualization to the user of how the scannercomponents can move during an imaging scan. The AR system may display agraphical object that indicates to the user the location of a space,defined by motion of the scanner components, in which a surgical tableor other object can be positioned while avoiding possible collision withthe movable scanner components during an imaging scan. The AR system maydisplay a graphical object that highlights a physical object that is ina collision pathway of the movable components. The AR system may displayvirtual imaging signal beams that extend between a pair of an imagingsignal transmitter and a detector panel which are located at presentlocations, defined previous locations, and/or defined future locations,to facilitate the user's positioning of these components relative to apatient. As used herein, a “user” may be, but is not limited to, aphysician, nurse, or other medical professional.

As will be explained in further detail below, an AR system obtains adigital image from a camera, such as from a camera mounted on an ARheadset or on a tripod, and identifies a pose of a gantry of a medicalimaging scanner based on content of the digital image. As used herein,the term pose refers to the dimensional location and/or angularorientation of an object. The gantry includes a movable C-arm supportingan imaging signal transmitter and a detector panel that are movablealong an arc relative to a station. A range of motion of the movableC-arm along the arc is determined based on the pose. A graphical objectis generated based on the range of motion and the pose, and is providedto a display device, such as to a display screen of an AR headset or toa graphics layer superimposed on a video stream layer on a computermonitor, for display as an overlay on the view of the portable medicalimaging scanner.

Various further embodiments are directed to displaying an arcuate objectas an overlay relative to the gantry and with a pose that indicates arange of motion of at least one of the imaging signal transmitter andthe detector panel. A circular object may be displayed with a pose thatindicates an interior region of the movable C-arm that will not becontacted by the imaging signal transmitter and/or the detector panelwhen moved along the arc through the range of motion. The system mayperform a collision alert action responsive to determining that aphysical object, which is separate from the gantry, has a surface thatextends from a location within the circular object displayed on thedisplay device to another location that is outside the circular object.The collision alert action may include displaying another graphicalobject overlaid relative to the physical object and that identifies thephysical object as being a collision risk, and/or may includecommunicating a command to the portable medical imaging scanner thatdisables electronic movement of the movable C-arm at least in adirection that may collide with the physical object. The system maygenerate an animation of the motion of the gantry through its range ofmotion. The system may display virtual imaging signal beams that extendbetween the present locations of the X-ray beam and the detector paneland/or that extend between earlier defined locations of the X-ray beamand the detector panel. These and additional embodiments are describedin further detail below.

In the following description, the components and operation of an examplemedical imaging scanner system are described with reference to FIGS. 1through 9G. An AR system is then described with reference to FIGS. 10through 16 and which may be used with the medical imaging scanner shownin FIGS. 1 through 9G.

Example Medical Imaging Scanner System

FIG. 1 is a schematic diagram showing a medical imaging scanner system10 (also “scanner system”), such as a computerized tomographic (CT)x-ray scanner, in accordance with one embodiment of the disclosure. Theimaging system 10 includes a movable station 60 and a gantry 56. Themovable station includes a vertical shaft 59 and a gantry mount 58 whichis rotatably attached to the vertical shaft. The movable station 60includes two front omni-directional wheels 62 and two rearomni-directional wheels 64, which together provide movement of themovable station 60 in any direction in an X-Y plane. The horizontal X-Yplane is depicted in the Cartesian coordinate system X, Y axes shown inFIG. 1, along with a vertical axis Z. The omni-directional wheels 62, 64can be obtained, for example, from Active Robots Limited of Somerset,U.K. A pair of handles 13 mounted to the housing of the movable station60 allow a user to manually maneuver the station.

A motor 66 attached to the vertical shaft 59 is designed to rotate thegantry mount 58 full 360 degrees about the X-axis and a motor 67 movesthe gantry mount 58 vertically along the z-axis under the control of themotion control module 51.

The gantry 56 includes a first C-arm 70 slidably coupled to the gantrymount 58 and a second C-arm 72 which is slidably coupled to the firstC-arm. In the embodiment shown, the first and second C-arms 70, 72 areouter and inner C-arms, respectively. In the embodiment shown, the outerand inner C-arms 70, 72 are partially-circular in shape and rotatecircumferentially about a central axis so as to allow imaging of apatient who is lying in bed 26 without the need to transfer the patient.

An imaging signal transmitter 74 such as an X-ray beam transmitter ismounted to one side of the second C-arm 72 while a detector panel 76such as an X-ray detector array is mounted to the other side of thesecond C-arm and faces the transmitter 74. In one embodiment, theimaging signal transmitter 74 transmits an X-ray beam for receipt by anX-ray detector component of the detector panel 76 after passing througha relevant portion of a patient (not shown) who is supported by thetable 26.

In one embodiment, the system 10 is a multi-modality x-ray imagingsystem which can be used during surgery. Imaging modalities may include,but are not limited to, fluoroscopy, 2D Radiography, and Cone-beam CT.Fluoroscopy is a medical imaging technique that shows a continuous X-rayimage on a monitor, much like an X-ray movie. 2D Radiography is animaging technique that uses X-rays to view the internal structure of anon-uniformly composed and opaque object such as the human body. CBCT(cone beam 3D imaging or cone beam computer tomography) also referred toas C-arm CT, is a medical imaging technique consisting of X-ray computedtomography where the X-rays are divergent, forming a cone. Magneticresonance imaging (MRI) may also be employed, with suitable precautionsfor using powerful magnets and controlling the magnetic fields theygenerate.

The movable station 60 includes an imaging controller system 40 whichmay serve a dual operational function of (1) controlling the movement ofthe omni-directional wheels 62, 64, gantry mount 58 and the gantry 56 toposition the imaging signal transmitter 74 in relation to the patient,and other component movements as needed, and (2) controlling imagingfunctions for imaging the patient once proper positioning has beenachieved.

Referring now to FIG. 2, the imaging controller system 40 is connectedto a communication link 52 through a network I/O interface 42 such as aUSB (universal serial bus) interface, which receives information fromand sends information over the communication link 52. The imagingcontroller system 40 includes memory storage 44 such as RAM (randomaccess memory), processor (CPU) 46, program storage 48 such as ROM orEEPROM, and data storage 50 such as a hard disk, all commonly connectedto each other through a bus 53. The program storage 48 stores, amongothers, imaging control module 54 and motion control module 51, eachcontaining software to be executed by the processor 46. The motioncontrol module 51 executed by the processor 46 controls the wheels 62,64 of the movable station 60 and various motors in the gantry mount 58and gantry 56 to position the station 60 near the patient and positionthe gantry in an appropriate position for imaging a relevant part of thepatient. The motion control module may also control additionalcomponents used for positioning, as explained below.

The imaging control module 54 executed by the processor 46 controls theimaging signal transmitter 74 and detector panel 76 to image the patientbody. In one embodiment, the imaging control module images differentplanar layers of the body and stores them in the memory 44. In addition,the imaging control module 54 can process the stack of images stored inthe memory 44 and generate a three dimensional image. Alternatively, thestored images can be transmitted through the network I/O interface 42 toa host system (not shown) for image processing.

The motion control module 51 and imaging control module 54 include auser interface module that interacts with the user through the displaydevices 11 a and 11 b and input devices such as keyboard and buttons 12and joy stick 14. Strain gauges 13 mounted to the handles 15 are coupledto the I/O device 42 and conveniently provide movement of the movablestation 12 in any direction (X, Y, Wag) while the user is holding thehandles 15 by hand, as will be discussed in more detail below. The userinterface module assists the user in positioning the gantry 56. Any ofthe software program modules in the program storage 48 and data from thedata storage 50 can be transferred to the memory 44 as needed and isexecuted by the CPU 46. The display device 11 a is attached to thehousing of the movable station 60 near the gantry mount 58 and displaydevice 11 b is coupled to the movable station through three rotatabledisplay arms 16, 18 and 20. First display arm 16 is rotatably attachedto the movable station 60, second display arm 18 is rotatably attachedto the first arm 16 and third display arm 20 is rotatably attached tothe second display arm. The display devices 11 a, 11 b can have touchscreens to also serve as input devices through the use of user interfacemodules in the modules 51 and 54 to provide maximum flexibility for theuser.

Navigation markers 68 may be connected to the gantry mount 58 and may beconnected to the imaging controller system 40 through the link 52. Underthe control of the motion control module 51, the markers 68 allowautomatic or semi-automatic positioning of the gantry 56 in relation tothe patient bed or (operating room) table via a navigation system (notshown). The markers 68 can be configured to have their pose opticallytracked, electromagnetically tracked, radiofrequency tracked (e.g.,triangulation based on time-of-arrival of defined signals atspaced-apart receivers or from spaced-apart transmitters), or the like.The markers may also be connected to other convenient and useful places,e.g., on the patient bed, or otherwise, so that the marker or markerswill be visible in the images taken and may be used to orient connectingimages when more than one image is taken of a patient, or other objectto be imaged. The markers may also contribute to merging or coordinatingmultiple images when more than one image is taken.

Information can be provided by the navigation system to command thegantry 56 or system 10 to precise locations. In one example, a surgeonholds a navigated probe at a desired orientation for the imaging system10 to acquire a fluoroscopic or radiographic image along that specifiedtrajectory. Advantageously, this method of defining the trajectory of anx-ray shot will remove the need for scout shots thus reducing x-rayexposure to the patient and operating room (OR) staff. The navigationmarkers 68 on the gantry 56 will also allow for automatic registrationof 2D or 3D images acquired by the system 10. The markers 68 will alsoallow for precise repositioning of the system 10 in the event thepatient has moved. The markers may be radiopaque or made from othermaterial that makes coordination or navigation easy for the imagingspecialists or other medical professionals. The navigation probes ormarkers may be placed as desired, e.g., nearby or on the object to beimaged, so that the markers do not interfere with the imaging or itsinterpretation.

In the embodiment shown, the system 10 provides a large range of motionin the 6-degrees of freedom (“DOF”) described below. Under the controlof the motion control module 51, there are two main modes of motion:positioning of the movable station 60 and positioning of the gantry 56.Other positioning modes are described and may also be included.

The movable station 60 positioning is accomplished via the fouromni-directional wheels 62, 64. These wheels 62, 64 allow the movablestation 60 to be positioned in all three DOF about the horizontal plane(X, Y, Wag). “Wag” is a system 10 rotation about the vertical axis(Z-axis), “X” is a system forward and backward positioning along theX-axis, and “Y” is system 10 lateral motion along the Y-axis. Under thecontrol of the control module 51, the system 10 can be positioned in anycombination of X, Y, and Wag (Wag about any arbitrary Z-axis due to useof omni-directional wheels 62, 64) with unlimited range of motion. Inparticular, the omni-directional wheels 62, 64 allow for positioning intight spaces, narrow corridors, or for precisely traversing up and downthe length of an OR table or patient bed.

The gantry 56 positioning is accomplished about (Z, Tilt, Rotor). “Z” isgantry 56 vertical positioning, “Tilt” is rotation about the horizontalaxis parallel to the X-axis as described above, and “Rotor” is rotationabout the horizontal axis parallel to the Y-axis as described above.

Together with the movable station 60 positioning and gantry 56positioning, the system 10 provides a range of motion in six DOF (X, Y,Wag, Z, Tilt and Rotor) to place the movable station 60 and the imagingsignal transmitter 74 and detector panel 76 precisely where they areneeded. Advantageously, 3-D imaging can be performed regardless ofwhether the patient is standing up, sitting up or lying in bed andwithout having to move the patient.

Precise positions of the system 10 can be stored in the storage memory50 and recalled at any time by the motion control module 51. This ispositional storage mechanism not limited to gantry 56 positioning butalso includes system 10 positioning due to the omni-directional wheels62, 64, and other axes of motion, as described below.

As shown in FIG. 3, each of the gantry mount 58, outer C-arm 70 andinner C-arm 72 respectively has a pair of side frames 86, 88, 90 thatface each other. A plurality of uniformly spaced rollers 84 are mountedon the inner sides of the side frames 86 of the gantry mount 58. Theouter C-arm 70 has a pair of guide rails 78 on the outer sides of theside frames 88. The rollers 84 are coupled to the guide rails 78. Asshown, the rollers 84 and the guide rails 78 are designed to allow theouter C-arm 70 to telescopically slide along the gantry mount 58 throughits permitted range of motion so as to permit a range of motion of atleast a 180 degree rotation of the C-arm about its central axis relativeto the gantry mount.

A plurality of uniformly spaced rollers 80 are mounted on the innersides of the side frames 88 of the outer C-arm 70. The inner C-arm 70has a pair of guide rails 82 on the outer sides of the side frames 90.The rollers 80 are coupled to the guide rails 82. As shown, the rollers80 and the guide rails 82 are designed to allow the inner C-arm 72 totelescopically slide along the outer C-arm 70 through its permittedrange of motion so as to permit a range of motion of at least 180 degreerotation of the C-arm about its central axis relative to the outerC-arm.

Thus, the present disclosure as disclosed herein advantageously allowsthe gantry 56 to rotate about its central axis through its permittedrange of motion, e.g., a full 360 degrees, to provide the maximumflexibility in positioning the imaging system 10 with minimumdisturbance of the patient.

In another aspect of the present disclosure, a unique cablingarrangement is provided to make the imaging system 10 more compact andvisually more appealing. As shown in FIGS. 5 and 6, a cablecarrier/harness 92 contains electrical cables to carry signals betweenthe imaging controller system 40 and various motors, X-ray transmitter74, detector panel 76 and various electronic circuits in the gantry 56.A first cable router 94 is mounted to the outer surface of the outerC-arm 70 and a second cable router 96 is mounted to the outer surface ofthe inner C-arm 72. Each cable router 94, 96 has a through-hole 95, 97through which the cable carrier 92 passes.

The cable carrier 92 extends from the gantry mount 56 over the outersurface of the first C-arm 70, through the through-hole 95 of the firstcable router 94 and over an outer surface of the second C-arm 72. Thecable carrier 92 overlying the first C-arm 70 extends in a firstcircumferential direction (clock-wise as shown) 98 and enters the firstcable router 94 in a second circumferential direction (counterclock-wise as shown) 99 opposite to the first circumferential directionto create a 180 degree service loop over the outer surface of the firstC-arm.

From there, the cable carrier 92 extends in the first circumferentialdirection 98 and enters the second cable router in the secondcircumferential direction 99 to create another service loop over theouter surface of the second C-arm 72.

The particular locations of the first and second cable routers 94, 96combined with the service loops allow slack in the cable carrier 92 toprovide the gantry 56 with full 360 degrees rotation without tangling orcausing stress in the cable carrier. In the embodiment shown, therouters are mounted near the midpoint of the C-arms.

FIG. 8 illustrates one embodiment of a motor assembly 100 that may beused for telescopically rotating the outer C-arm 70 relative to thegantry mount 58 and for rotating the inner C-arm 72 relative to theouter C-arm. Each motor assembly 100 includes a servo motor 102 withencoder feedback, gear box 104 to change the turning ratio, drive pulley106, idler pulleys 108 and belt 110 threaded between the drive pulleyand the idler pulleys. One motor assembly 100 is mounted to the gantrymount to move the outer C-arm 70 along an arc relative to the gantrymount and another motor assembly is mounted to the outer C-arm 70 nearthe center of the arm to move the inner C-arm 70 along the arc relativeto the outer C-arm.

FIGS. 9A-9G illustrate the 360 degree rotation of the gantry 56 in thecounter-clockwise direction in 60 degree increments along its arcuaterange of motion. FIG. 9A represents a zero degree position of thedetector panel 76 and imaging signal transmitter 74. FIG. 9B representsa 60 degree turn/position of the gantry 56. For each 60 degree turn ofthe gantry 56, the motor assemblies 100, under the control of the motioncontrol module 51, turn the inner C-arm 72 by 30 degrees counter-clockwise along the arc while also turning the outer C-arm 70 by 30 degreescounter-clock wise along the arc for a combined 60 degree turn. FIG. 9Grepresents a full 360 degree turn of the gantry 56 through its range ofmotion along the arc. As can be seen, the outer C-arm 70 and inner C-arm72 have each moved 180 degrees from the original zero degree position ofFIG. 9A. Note that the transmitter 74 and detector panel 76 in FIGS. 9Dand 9G are reversed from their positions in FIGS. 1 and 9A. Thisreversal may be advantageous, for example, when it is desirable to havethe imaging signal transmitter on one particular side or to have thedetector panel on one particular side.

AR System for Use with Medical Imaging Scanner System

Embodiments of an AR system 1060 are now described with reference toFIGS. 10 through 16 and which may be used with the medical imagingscanner shown in FIGS. 1 through 9G. FIG. 10 is a perspective rear viewof an AR system 1060 with an AR headset 1000. The AR system 1060 enablesa user who is wearing the AR headset 1000 to visually observe graphicalobjects that are displayed as an overlay on the medical imaging scanner10 to illustrate the range of motion and related operations of themovable scanner components. The graphical objects may provide predictivevisualization to the user of how the scanner components can move duringan imaging scan.

Although some operational embodiments are discussed in the context of anAR system that displays graphics on a see-through display screen of anAR headset, the disclosed operations may additionally or alternativelybe used to display graphics on other types of display screens, such asthe displays 11 a and 11 b connected to the movable station 60 and/orother displays mounted elsewhere in the operating room.

When setting up the imaging scanner 10 for use, the C-arms 70 and 72, towhich the imaging signal transmitter 74 and detector panel 76 aremounted, come in from the side of the table 26. Then, during an imagingscan, the C-arms 70 and 72 automatically rotate in a circle around animaging center, where a patient may reside on a table 26. Predictivevisualization can be beneficially used during setup to visualize therange of motion and arcuate paths of the C-arms 70 and 72 if they wereto move during an imaging scan. The AR system 1060 enables a user,without operationally starting an imaging scan, to visualize if one orboth of the C-arms 70 and 72 is able to clear any obstructions in thepath, such as the table 26, a patient, and/or other adjacent objects orequipment.

In a first approach, the AR system 1060 determines the range of motionand the translational and/or rotational movement of the scannercomponents during a scan, using a defined physical and operational modelof relevant characteristics of the components and the supportingC-arm(s), and which may also model their operational environment (e.g.,relative motion, speed, and/or acceleration). The AR system 1060 maydisplay on the display screen 1020 a graphical animation of the movablecomponents moving through their arcuate path. A potential disadvantageof this approach is that it relies on a detailed physical andoperational model of the imaging system 10, which is limited to use withthat particular type of imaging system.

In a second approach, the AR system 1060 performs image processing ofthe digital images from the camera 1010 to identify a feature of thegantry 56, such as detectable features (e.g., edges) of tracks, theimaging signal transmitter 74, the detector panel 76, or the C-arm(s) 70and/or 72. The identified feature is used to determine a pose (i.e.,dimensional location and/or angular orientation) of the movablecomponent of the imaging scanner 10, such as a pose of the imagingsignal transmitter 74 and/or the detector panel 76. Alternatively oradditionally, the image processing can identify within the digital imagefrom the camera 1010 a location and orientation of a plurality ofspaced-apart navigation markers connected to the gantry 56, and identifya pose of at least one of the imaging signal transmitter 74 and thedetector panel 76 based on the location and orientation of the pluralityof spaced-apart tracking markers. If these tracking markers are spacedin a particular unique pattern, the tracking system can use the spacingpattern to detect and identify the location of the component to whichthe markers are attached. The second approach is further described belowwith reference to FIGS. 10 and 17, although various of the describedoperations may also be used with the first approach. FIG. 17 is aflowchart of operations and methods that may be performed by the ARsystem 1060.

Referring to FIGS. 10 and 17, the AR headset 1000 includes a displayscreen 1020, a camera 1010, and a processor 1510 (shown in FIG. 15)which are connected to and supported by a headset frame 1002. The camera1010 outputs a digital image that may be a single image or a frame of avideo stream. In the illustration of FIG. 10 the camera 1010 outputs1700 a digital image of the medical imaging scanner 10 within thefield-of-view of the camera 1010. Content of the digital image isprocessed to identify 1702 a pose of the gantry 56 of the medicalimaging scanner 10. As explained above, the gantry 56 includes a movableC-arm (e.g. first C-arm 70 and second C-arm 72) that supports an imagingsignal transmitter 74 and a detector panel 76 that are movable along anarc relative to the station 60. A range of motion of the movable C-armalong the arc is operationally determined 1704 based on the pose. Agraphical object is operationally generated 1706 based on the range ofmotion and the pose, and is provided 1708 to the display screen 1020 fordisplay as an overlay relative to the medical imaging scanner 10.

Any one or more of the operations for identifying a pose of the gantry56, determining the range of motion of the movable C-arm, generating thegraphical object, and/or providing the graphical object to the displayscreen 1020 may be performed by the processor 1510 local to the ARheadset 1000 and/or by another processor that is external to the ARheadset 1000 and communicatively connected thereto, such as by aprocessor of an AR predictive visualization computer 1050 (e.g.,processor 1610 shown in FIG. 16). The computer 1050 may, for example, bea desktop computer, laptop computer, tablet computer, cellular phone, anetwork server, or other digital processing device. The AR headset 1000may be any type of AR headset that is configured to display a graphicalobject on a display screen that may be seen-through by a user, such asthe Google Glass AR headset.

To provide predictive visualization for the imaging scanner 10 and, moreparticularly, its components that are moved during scanning (“movablecomponents”), e.g., imaging signal transmitter 74 and/or detector panel76, the AR system 1060 obtains information that defines the range ofmotion and other related characteristics of the movable components. Forexample, when the detector panel 76 and the imaging signal transmitter74 are connected to the first C-arm 70 and the second C-arm 72,respectively, and constrained to travel along an arcuate rail, the ARsystem generates predictive visualization of motion of the detectorpanel 76 and the imaging signal transmitter 74 using a transformationmatrix. The transformation matrix is used to mathematically transformthe positions and angular orientations for one or more components, e.g.the detector panel 76 and the imaging signal transmitter 74, referencedin the coordinate system of the rail to the corresponding positions andangular orientations referenced in the coordinate system of the ARheadset 1000. Another transformation matrix can be similarly used totransform the position and/or angular orientation referenced in thecoordinate system of the AR headset 1000 to the corresponding positionsand/or angular orientations referenced in the coordinate system of therail and/or another coordinate system defined by the AR system 1060.

The information obtained by the AR system 1060 may define how one ormore of the movable components translationally moves and/or rotateswhile traveling through its range of motion along the rail. Theinformation may further define the speed and/or acceleration with whichthe one or more movable components travels, which is used to generatethe graphical objects that are displayed on the display screen 1020 toprovide predictive visualization of such movement.

The AR headset 1000 may display a graphical object that indicates to theuser the location of a space, defined by motion of the scannercomponents, in which the surgical table 26 or other physical object canbe positioned while avoiding possible collision with the movable scannercomponents during an imaging scan. In one embodiment, the AR headset1000 displays a graphical object that indicates to the user the locationof a space, defined by motion of the detector panel 76 and the imagingsignal transmitter 74, in which the surgical table 26 or other physicalobject can be positioned while avoiding possible collision with thesecomponents during an imaging scan. FIG. 11 is a side view of the gantry56 as viewed through the display screen 1020 of the AR headset 1000 thatdisplays a graphical object illustrating an interior region of themovable C-arms 70 and 72 that will not be contacted by the movablecomponents when moved through their range of motion during a scan.

Referring to FIG. 11, the AR system 1060 displays a circular object 1100as an overlay relative to the gantry 56 and with a pose (i.e.,dimensional location and/or angular orientation) that indicates aninterior region of the circle that will not be contacted by the imagingsignal transmitter 74 and/or the detector panel 76 when they are movedalong the arc through their range of motion during an imaging scan. Therelated operations perform by the AR system 1060 can include identifyingthe pose of the gantry 56 based on identifying a pose of the imagingsignal transmitter 74 and/or the detector panel 76. The range of motionof the imaging signal transmitter 74 and/or the detector panel 76 alongthe arc is determined based on the pose. An arcuate object, e.g.,circular object 1100, is generated and provided to the display screen1020 for display as an overlay relative to the gantry 56 and with a posethat indicates the range of motion of the imaging signal transmitter 74and/or the detector panel 76 along the arc. Accordingly, the user canview the imaging scanner 10 through the display screen 1020 to determinewhere the table 26, a patient, and/or other objects can be placed withinthe displayed interior region 1100 without risk of collision withmovable components of the imaging scanner 10 during a scan. Or when theuser looks at the scene through AR glasses with the patient on thetable, if any part of the patient or table appears to be outside thatcircle, which is overlaid on the scene, the user can adjust the positionof the imaging system or the position of the table.

The AR system 1060 may perform a collision alert action responsive todetermining that a physical object 1110 which is separate from thegantry 56 has a surface that extends from a location within the circularobject 1100 displayed on the display screen 1020 to another location1120 that is outside the circular object 1100.

In one embodiment, the collision alert action performed by the AR system1060 generates another graphical object that is provided for display onthe display screen 1020 as an overlay relative to the physical objectand that identifies the physical object as being a collision risk. FIG.12 is a side view of the gantry 56 as viewed through the display screen1020 that displays a graphical object indicating that the surgical table26 has a risk of collision with the movable components when they aremoved through their range of motion. In the illustration of FIG. 12, theAR system 1060 has identified through the digital picture from thecamera 1010 that the table 26 is located in the pathway of the C-arm(s)70,72 during an imaging scan and, responsive thereto, has displayedbrightly colored or flickering rays 1200 overlaid with a top surface ofthe table 26 to draw the user's attention to the risk that an endportion 1210 of the C-arm 70 will impact the top surface of the table26. Other graphical objects may be generated by the AR system 1060 toalert the user as to the risk of collision with an object that isidentified through the digital picture from the camera 1010 as beingwithin a pathway of the movable components of the gantry 56.

In another embodiment, the collision alert action performed by the ARsystem 1060 communicates a command to the medical imaging scanner 10that disables electronic movement of the gantry 56 for an imaging scanand, more particularly, the movable C-arms 70 and 72, at least in adirection that may collide with the physical object. The AR system 1060may communicate another command to the medical imaging scanner 10 thatre-enables electronic movement of the gantry 56 when another digitalpicture from the camera 1010 indicates that the physical object is nolonger in a pathway of the movable components of the gantry 56.

In another embodiment, the AR system 1060 changes sets a color of thecircular object 1100 to indicate whether there is a risk of the movablecomponents colliding with a physical object. For example, the circularobject 1100 may be rendered in a green color when no risk of collisionis identified and, in contrast, rendered in a red color when a risk ofcollision is identified.

The AR system 1060 may provide graphical animation through the displayscreen 1020 that shows the user a predictive visualization of how themoving components of the gantry 56 will move along their pathways duringan imaging scan. The operations by the AR system 1060 can includedetermining a range of motion of an end of the movable C-arm along thearc, e.g., end 1210. The operation of providing the graphical object tothe display screen 1020 include displaying a graphical object as anoverlay that extends from a present location of the ends of the movableC-arms 70 and 72 to a spaced-apart location along the arc that is withintheir ranges of motion during a scan. For example, the AR system 1060may graphically animate rotation of the C-arms 70 and 72 from a fullyretracted position to a fully extended position.

While providing a graphical animation of the movable components of thegantry 56, the AR system 1060 may also determine that a physical object,which is separate from the gantry 56, has a surface that is intersectedby one of the graphical objects being moved in the animation and,responsive thereto, provide another graphical object for display on thedisplay screen 1020 as an overlay relative to the physical object thatidentifies the physical object as being a collision risk for one or moreof the movable components, such as an end of the movable C-arm, whenmoved along the arc through its range of motion.

In another embodiment, while providing a graphical animation of themovable components of the gantry 56, the AR system 1060 may alsodetermine that a physical object, which is separate from the gantry 56,has a surface that is intersected by one of the graphical objects beingmoved in the animation and, responsive thereto, communicating a commandto the medical imaging scanner 10 that disables electronic movement ofthe gantry 56 for an imaging scan (e.g., the movable C-arms 70 and 72)at least in a direction that may collide with the physical object.

Some other embodiments are directed to the AR system 1060 displayinggraphical representations of the imaging signal transmitter 74 and thedetector panel 76 that are rotated to one or more defined locations. Forexample, while viewing the imaging scanner 10 through the display screen1020, the AR system 1060 may display graphical objects that show wherethe imaging signal transmitter 74 and the detector panel 76 were locatedalong the arc during a previous imaging scan, and/or where they need tobe rotated to perform a next imaging scan at a desired offset anglethrough a patient. Enabling a user to view graphical representations ofthe imaging signal transmitter 74 and the detector panel 76 from a priorimaging scan can allow the user to optimally position those componentsfor a subsequent lateral scan and/or anteroposterior scan centered onthe anatomy of interest.

The related operations performed by the AR system 1060 are explainedbelow with reference to FIG. 13. FIG. 13 is a side view of the gantry 56as viewed through a display screen 1020 that displays graphical objectswhich illustrate earlier defined locations and/or future definedlocations of the imaging signal transmitter 74 and the detector panel76. The operations can include identifying a pose (i.e., dimensionallocation and/or angular orientation) of at least one of the imagingsignal transmitter 74 and the detector panel 76. A first graphicalobject 1374 is generated that represents the imaging signal transmitter74 and has a first pose that is rotated and offset to a first locationalong the arc relative to a present location of the imaging signaltransmitter 74. Similarly, a second graphical object 1376 is generatedthat represents the detector panel 76 and has a second pose that isrotated and offset to a second location along the arc relative to apresent location of the detector panel 76. The first and secondgraphical objects 1374 and 1376 are provided to the display screen 1020for display as an overlay relative to the gantry 56 and with therespective first and second poses.

The operations of generating the graphical object can be repeated for aplurality of locations along the arc, with the generated graphicalobjects being provided to the display screen 1020 to animate repetitivemovement of the imaging signal transmitter 74 and the detector panel 76through at least part of the range of motion along the arc.

Some other embodiments are directed to the AR system 1060 displayingvirtual imaging signal beams that extend between the imaging signaltransmitter 74 and the detector panel 76 according to their presentlocations, defined previous locations, and/or defined future locations,to facilitate the user's positioning of these components relative to apatient to perform a sequence of imaging scans. Enabling a user to viewvirtual imaging signal beams can allow the user to optimally positionthe imaging signal transmitter 74 and the detector panel 76 for alateral scan and/or anteroposterior scan centered on the anatomy ofinterest. For example, moving from an anterior-posterior scan positionto a lateral scan position occurs with the AR headset 1000 displaying avirtual imaging signal beam of the imaging signal transmitter 74 from aprior imaging position, so that the operator may rotate the C-arm to adesired offset angle relative to the earlier scan and centered on theanatomy of interest.

Various related operations are described with reference to FIG. 14. FIG.14 is a side view of the gantry 56 as viewed through the display screen1020 that displays a virtual imaging signal beam extending between thepresent locations of the imaging signal transmitter 74 and the detectorpanel 76, and displays another virtual imaging signal beam that extendsbetween earlier defined locations of the imaging signal transmitter 74and the detector panel 76.

The operations performed by the AR system 1060 to identify the pose ofthe gantry 56 can include identifying present locations of the imagingsignal transmitter 74 and the detector panel 76. Generation of agraphical object can include generating a second virtual imaging signalbeam 1410 that is provided to the display screen 1020 for display as anoverlay relative to the gantry 56 and extending from a present locationof the imaging signal transmitter 74 to a present location of thedetector panel 76. Generation of a graphical object may alternatively oradditionally include generating a first virtual imaging signal beam 1420that is provided to the display screen 1020 for display as an overlayrelative to the gantry 56 and extending from an earlier defined locationof the imaging signal transmitter 74 to an earlier defined location ofthe detector panel 76. The earlier defined location locations maycorrespond to where the imaging signal transmitter 74 and detector panel76 were previously located during an earlier imaging scan. Accordingly,a user who is looking through the display screen 1020 at the gantry 56can visually observe the location of the first virtual imaging signalingbeam 1420 while rotating the gantry 56 to position the imaging signaltransmitter 74 and detector panel 76 to the location where the secondvirtual imaging signal beam 1410 is visually observed as intersectingthe first virtual imaging signal beam 1420 with an angle that isdesired, e.g., about 90 degrees, for a next imaging scan.

As explained above, the operations disclosed herein may be used todisplay graphics on the displays 11 a and 11 b connected to the movablestation 60 and/or on other displays mounted elsewhere in the operatingroom. The AR system 1060 can include a camera that is connected to atripod or other structure and positioned to view the medical imagingscanner 10 and to output a video stream of digital image frames showingthe medical imaging scanner 10. The predictive visualization system 1050is connected to receive the video stream from the camera, and to addgraphical objects positionally overlaid on the digital image framesrelative to the medical imaging scanner 10 to generate a composite videostream that is provided to the display(s), e.g., displays 11 a and 11 band/or other displays. The graphical objects added to form the compositevideo stream can illustrate the path of the movable components of thescanner 10 and related collision risks, past and/or target futurelocations of the movable components, and/or related virtual imagingsignal beams in accordance with any one or more of the embodimentsdisclosed herein.

Accordingly, various embodiments disclosed herein provide an improveduser interface for operating a medical imaging system. The AR system1060 provides an intuitive user interface that can improve safety ofoperation of the medical imaging system and improve quality of theimages that are generated from a sequence of image scans through apatient at different angles.

Components of AR Headset and AR Predictive Visualization Computer

FIG. 15 is a block diagram that illustrates components of an AR headset1000 that is configured in accordance with some embodiments. The ARheadset 1000 can include a camera 1010, a display screen 1020, at leastone processor circuit 1510 (processor), and at least one memory 1520(memory). The display screen 1020 may be a see-through screen thatdisplays graphical images for viewing by a user while allowingtransmission of incident ambient light from physical objects to passtherethrough to the user for viewing. The processor is connected to thecamera 1010, the display screen 1020, and the memory 1520. The memory1520 stores program code 1522 that is executed by the processor 1510 toperform operations. The processor 1510 may include one or more dataprocessing circuits, such as a general purpose and/or special purposeprocessor (e.g., microprocessor and/or digital signal processor), whichmay be collocated or distributed across one or more data networks. Theprocessor 1510 is configured to execute computer program instructionsamong program code 1522 in the memory 1520, described below as acomputer readable medium, to perform some or all of the operations andmethods for one or more of the embodiments disclosed herein for a ARheadset 1000. They are headset 1000 may include a wireless and/or wirednetwork interface circuit 1530 that is configured to communicate withanother electronic device, such as the AR predictive visualizationcomputer 1050 and/or the imaging scanner 10, through a wired (e.g.,ethernet, USB, etc.) and/or wireless (e.g., Wi-Fi, Bluetooth, cellular,etc.) network.

FIG. 16 is a block diagram that illustrates components of an ARpredictive visualization computer 1050 that is configured in accordancewith some embodiments. The computer 1050 can include a wireless and/orwired network interface circuit 1630, at least one processor circuit1610 (processor), and at least one memory 1620 (memory). The networkinterface circuit 1630 is configured to communicate with anotherelectronic device, such as the AR headset 1000 and/or the imagingscanner 10, through a wired (e.g., ethernet, USB, etc.) and/or wireless(e.g., Wi-Fi, Bluetooth, cellular, etc.) network. The processor 1610 isconnected to network interface 1630 in the memory 1620. The memory 1620stores program code 1622 that is executed by the processor 1610 toperform operations. The processor 1610 may include one or more dataprocessing circuits, such as a general purpose and/or special purposeprocessor (e.g., microprocessor and/or digital signal processor), whichmay be collocated or distributed across one or more data networks. Theprocessor 1610 is configured to execute computer program instructionsamong program code 1622 in the memory 1620, described below as acomputer readable medium, to perform some or all of the operations andmethods for one or more of the embodiments disclosed herein for an ARpredictive visualization computer.

When the AR predictive visualization system 1050 is used with a non-headmounted display and camera, the display and camera may be connected tothe processor circuitry 1610 through the network interface circuitry1630 which can include parallel video input and output circuits, such asHDMI, DisplayPort, Digital Visual Interface, and/or other videointerface circuitry.

FURTHER DEFINITIONS AND EMBODIMENTS

In the above description of various embodiments of the presentdisclosure, aspects of the present disclosure may be illustrated anddescribed herein in any of a number of patentable classes or contextsincluding any new and useful process, machine, manufacture, orcomposition of matter, or any new and useful improvement thereof.Accordingly, aspects of the present disclosure may be implemented inentirely hardware, entirely software (including firmware, residentsoftware, micro-code, etc.) or combining software and hardwareimplementation that may all generally be referred to herein as a“circuit,” “module,” “component,” or “system.” Furthermore, aspects ofthe present disclosure may take the form of a computer program productcomprising one or more computer readable media having computer readableprogram code embodied thereon.

Any combination of one or more computer readable media may be used. Thecomputer readable media may be a computer readable signal medium or acomputer readable storage medium. A computer readable storage medium maybe, for example, but not limited to, an electronic, magnetic, optical,electromagnetic, or semiconductor system, apparatus, or device, or anysuitable combination of the foregoing. More specific examples (anon-exhaustive list) of the computer readable storage medium wouldinclude the following: a portable computer diskette, a hard disk, arandom access memory (RAM), a read-only memory (ROM), an erasableprogrammable read-only memory (EPROM or Flash memory), an appropriateoptical fiber with a repeater, a portable compact disc read-only memory(CD-ROM), an optical storage device, a magnetic storage device, or anysuitable combination of the foregoing. In the context of this document,a computer readable storage medium may be any tangible medium that cancontain, or store a program for use by or in connection with aninstruction execution system, apparatus, or device.

A computer readable signal medium may include a propagated data signalwith computer readable program code embodied therein, for example, inbaseband or as part of a carrier wave. Such a propagated signal may takeany of a variety of forms, including, but not limited to,electro-magnetic, optical, or any suitable combination thereof. Acomputer readable signal medium may be any computer readable medium thatis not a computer readable storage medium and that can communicate,propagate, or transport a program for use by or in connection with aninstruction execution system, apparatus, or device. Program codeembodied on a computer readable signal medium may be transmitted usingany appropriate medium, including but not limited to wireless, wireline,optical fiber cable, RF, etc., or any suitable combination of theforegoing.

For purposes of this application, the terms “code”, “software”,“program”, “application”, “software code”, “software module”, “module”and “software program” are used interchangeably to mean softwareinstructions that are executable by a processor.

Computer program code for carrying out operations for aspects of thepresent disclosure may be written in any combination of one or moreprogramming languages, including an object oriented programming languagesuch as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C#, VB.NET,Python or the like, conventional procedural programming languages, suchas the “C” programming language, Visual Basic, Fortran 2003, Perl, COBOL2002, PHP, ABAP, dynamic programming languages such as Python, Ruby andGroovy, or other programming languages. The program code may executeentirely on the user's computer, partly on the user's computer, as astand-alone software package, partly on the user's computer and partlyon a remote computer or entirely on the remote computer or server. Inthe latter scenario, the remote computer may be connected to the user'scomputer through any type of network, including a local area network(LAN) or a wide area network (WAN), or the connection may be made to anexternal computer (for example, through the Internet using an InternetService Provider) or in a cloud computing environment or offered as aservice such as a Software as a Service (SaaS).

Aspects of the present disclosure are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of thedisclosure. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer program instructions. These computer program instructions maybe provided to a processor of a general purpose computer, specialpurpose computer, or other programmable data processing apparatus toproduce a machine, such that the instructions, which execute via theprocessor of the computer or other programmable instruction executionapparatus, create a mechanism for implementing the functions/actsspecified in the flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in a computerreadable medium that when executed can direct a computer, otherprogrammable data processing apparatus, or other devices to function ina particular manner, such that the instructions when stored in thecomputer readable medium produce an article of manufacture includinginstructions which when executed, cause a computer to implement thefunction/act specified in the flowchart and/or block diagram block orblocks. The computer program instructions may also be loaded onto acomputer, other programmable instruction execution apparatus, or otherdevices to cause a series of operational steps to be performed on thecomputer, other programmable apparatuses or other devices to produce acomputer implemented process such that the instructions which execute onthe computer or other programmable apparatus provide processes forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks.

It is to be understood that the terminology used herein is for thepurpose of describing particular embodiments only and is not intended tobe limiting of the invention. Unless otherwise defined, all terms(including technical and scientific terms) used herein have the samemeaning as commonly understood by one of ordinary skill in the art towhich this disclosure belongs. It will be further understood that terms,such as those defined in commonly used dictionaries, should beinterpreted as having a meaning that is consistent with their meaning inthe context of this specification and the relevant art and will not beinterpreted in an idealized or overly formal sense unless expressly sodefined herein.

The flowchart and block diagrams in the figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousaspects of the present disclosure. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof code, which comprises one or more executable instructions forimplementing the specified logical function(s). It should also be notedthat, in some alternative implementations, the functions noted in theblock may occur out of the order noted in the figures. For example, twoblocks shown in succession may, in fact, be executed substantiallyconcurrently, or the blocks may sometimes be executed in the reverseorder, depending upon the functionality involved. It will also be notedthat each block of the block diagrams and/or flowchart illustration, andcombinations of blocks in the block diagrams and/or flowchartillustration, can be implemented by special purpose hardware-basedsystems that perform the specified functions or acts, or combinations ofspecial purpose hardware and computer instructions.

The terminology used herein is for the purpose of describing particularaspects only and is not intended to be limiting of the disclosure. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items. Like reference numbers signify like elements throughoutthe description of the figures.

The corresponding structures, materials, acts, and equivalents of anymeans or step plus function elements in the claims below are intended toinclude any disclosed structure, material, or act for performing thefunction in combination with other claimed elements as specificallyclaimed. The description of the present disclosure has been presentedfor purposes of illustration and description, but is not intended to beexhaustive or limited to the disclosure in the form disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of thedisclosure. The aspects of the disclosure herein were chosen anddescribed in order to best explain the principles of the disclosure andthe practical application, and to enable others of ordinary skill in theart to understand the disclosure with various modifications as aresuited to the particular use contemplated.

What is claimed is:
 1. An augmented reality (AR) system for use with amedical imaging scanner, the AR system comprising: a processor; and amemory comprising program code that is executable by the processor toperform operations comprising: obtaining a digital image from a camera;identifying a pose of a gantry of the medical imaging scanner based oncontent of the digital image, the gantry including a movable C-armsupporting an imaging signal transmitter and a detector panel that aremovable along an arc relative to a station; determining a range ofmotion of the movable C-arm along the arc based on the pose; generatinga graphical object based on the range of motion and the pose; andproviding the graphical object to a display device for display as anoverlay relative to the medical imaging scanner, wherein the operationof identifying the pose of the gantry comprises identifying a pose of atleast one of the imaging signal transmitter and the detector panel,wherein the operation of determining the range of motion of the movableC-arm along the arc comprises determining a range of motion of the atleast one of the imaging signal transmitter and the detector panel alongthe arc; and wherein the operation of providing the graphical object tothe display device comprises providing an arcuate object for display asan overlay relative to the gantry and with a pose that indicates therange of motion of the at least one of the imaging signal transmitterand the detector panel along the arc; wherein the operation of providingthe arcuate object for display comprises providing a circular object fordisplay as an overlay relative to the gantry and with a pose thatindicates an interior region of the movable C-arm that will not becontacted by the at least one of the imaging signal transmitter and thedetector panel when moved along the arc through the range of motion. 2.The AR system of claim 1, further comprising: determining that aphysical object which is separate from the gantry has a surface thatextends from a location within the circular object displayed on thedisplay device to another location that is outside the circular object;and performing a collision alert action responsive to the determination.3. The AR system of claim 2, wherein: performing the collision alertaction comprises providing another graphical object for display as anoverlay relative to the physical object and that identifies the physicalobject as being a collision risk for the at least one of the imagingsignal transmitter and the detector panel when moved along the arcthrough the range of motion.
 4. The AR system of claim 2, wherein:performing the collision alert action comprises communicating a commandto the medical imaging scanner that disables electronic movement of themovable C-arm at least in a direction that may collide with the physicalobject.
 5. The AR system of claim 1, wherein: the operation ofdetermining the range of motion of the movable C-arm along the arccomprises determining a range of motion of an end of the movable C-armalong the arc; and the operation of providing the graphical object tothe display device comprises providing the graphical object to thedisplay device as an overlay that extends from a present location of theend of the movable C-arm to a spaced-apart location along the arc thatis within the range of motion of the end of the movable C-arm.
 6. The ARsystem of claim 5, further comprising: determining that a physicalobject that is separate from the gantry has a surface that isintersected by the graphical object; and providing another graphicalobject for display as an overlay relative to the physical object andthat identifies the physical object as being a collision risk for theend of the movable C-arm when moved along the arc through the range ofmotion.
 7. The AR system of claim 5, further comprising: determiningthat a physical object that is separate from the gantry has a surfacethat is intersected by the graphical object; and communicating a commandto the medical imaging scanner that temporarily disables electronicmovement of the movable C-arm at least in a direction that may collidewith the physical object, responsive to the determination that thesurface of the physical object is intersected by the graphical object.8. The AR system of claim 1, wherein: the operation of identifying thepose of the gantry comprises identifying a pose of at least one of theimaging signal transmitter and the detector panel; the operation ofgenerating the graphical object based on the range of motion and thepose, comprises generating a first graphical object that represents theimaging signal transmitter and has a first pose that is rotated andoffset to a first location along the arc relative to a present locationof the imaging signal transmitter, generating a second graphical objectthat represents the detector panel and has a second pose that is rotatedand offset to a second location along the arc relative to a presentlocation of the detector panel; and the operation of providing thegraphical object to the display device comprises providing the first andsecond graphical objects for display as an overlay relative to thegantry and with the respective first and second poses.
 9. The AR systemof claim 8, further comprising: repeating the operations of generatingthe graphical object for a plurality of locations along the arc and theproviding the graphical object to the display device to animaterepetitive movement of the imaging signal transmitter and the detectorpanel through at least part of the range of motion along the arc. 10.The AR system of claim 1, wherein: the operation of identifying the poseof the gantry comprises identifying present locations of the imagingsignal transmitter and the detector panel; the operation of generatingthe graphical object, comprises generating a first virtual imagingsignal beam and a second virtual imaging signal beam; and the operationof providing the graphical object to the display device comprises:providing the first virtual imaging signal beam for display as anoverlay relative to the gantry and extending from an earlier definedlocation of the imaging signal transmitter to an earlier definedlocation of the detector panel; and providing the second virtual imagingsignal beam for display as another overlay relative to the gantry andextending from a present location of the imaging signal transmitter to apresent location of the detector panel.
 11. The AR system of claim 10,wherein: the first and second virtual imaging signal beams are displayedrotationally offset from each other by about 90 degrees.
 12. The ARsystem of claim 1, wherein: the operation of identifying the pose of thegantry comprises identifying within the digital image a defined featureof the gantry, and identifying a pose of at least one of the imagingsignal transmitter and the detector panel based on a pose of the definedfeature within the digital image.
 13. The AR system of claim 1, wherein:the operation of identifying the pose of the gantry comprisesidentifying within the digital image a location and orientation of aplurality of spaced-apart navigation markers connected to the gantry,and identifying a pose of at least one of the imaging signal transmitterand the detector panel based on the location and orientation of theplurality of spaced-apart tracking markers.